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  • 1.  Precast Concrete Curbstone versus Curber Machine Mix Proportions

    Posted 02-06-2021 08:58 PM
    Does anyone have any information on the mix proportions and gravel size for the precast curbstone and how it differs from the curber machine's concrete?

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    Mohammed Al-Tofan Ph.D., P.E., M.ASCE
    West Columbia SC
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  • 2.  RE: Precast Concrete Curbstone versus Curber Machine Mix Proportions

    Posted 02-08-2021 07:57 PM
    I am not familiar with precast curb stones. Here in Michigan contractors use a curb slip form machine or handset the curb. The mix design is similar except the curb machine uses a much lower slump.

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    Douglas Skylis P.E., M.ASCE
    SR PROJ MANAGER
    Lapeer MI
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  • 3.  RE: Precast Concrete Curbstone versus Curber Machine Mix Proportions

    Posted 05-25-2021 03:39 PM
    Edited by Tirza Austin 05-25-2021 03:39 PM
    In our region, Curbstones shall only be precast from concrete mixture contain not less 400KG/m3 of sulphat Resisting Portland cement in which the compressive strength after 28 days should achieve minimum 45 N/mm2  and the concrete produced in a fully automatic batching plant and sampling shall be done and the materials (coarse and fine aggregate , cement and water) to be are selected in compliance with suitable international standard in order to specify suitable grading, ,fine aggregate % , coarse aggregate %, water absorption, specific gravity ,elongation index, soundness, Acid soluble upper range and lower range and the combined grading shall be within appropriate specified grading limits with Max. aggregate size of 20mm. We used to  use of precast Curb  rather than curber Machin's concrete and i believe that the main differences of the concrete mix in the two methods will be on the slump range and using different type of admixtures.

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    Ashraf Amin A.M.ASCE
    Chief Engineer for Roads and Infrastructure
    RTA- Dubai
    Dubai
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